Crystalline molecular sieves

ABSTRACT

MFS structure type zeolite manufacture is facilitated by using a second organic molecule in addition to the usual hexaethylpentane diammonium salt.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the U.S. National Stage of International ApplicationNo. PCT/GB02/04355, filed 27 Sep. 2002 which claims priority to EuropeanPatent Application No. 01308288.8, filed 28 Sep. 2001.

FIELD OF THE INVENTION

The present invention relates to a process for the preparation of acrystalline zeolite of the MFS structure type.

DESCRIPTION OF RELATED ART

Zeolites of the MFS structure type, and in particular ZSM-57, are usefulcatalyst components for a variety of conversion processes, such ashydrocarbon cracking, dehydrogenation, oligomerization, isomerization,disproportionation, and alkylation as well as the formation ofhydrocarbons from oxygen-containing compounds such as alcohols andethers.

The composition, properties and preparation of ZSM-57 are disclosed inEP-A-174 121, and U.S. Pat. Nos. 4,873,067 and 4,973,781, the entiredisclosures of these documents being incorporated by reference herein.ZSM-57 is a zeolite with a typical molar ratio of XO₂:Y₂O₃ of at least4, wherein X represents silicon and/or germanium and Y representsaluminium, boron, chromium, iron and/or gallium. Preferably, there arefrom greater than 8 to about 200 moles of X₂ per mole of Y₂O₃.Preferably, XO₂ is silica and Y₂O₃ is alumina.

ZSM-57 may be prepared as described in EP-A-174 121 from a synthesismixture containing sources of alkali metal ions, an oxide of silicon, anoxide of aluminium, water and an organic directing agent which is a saltof N,N,N,N′,N′,N′-hexaethylpentane diammonium (HEPD, also known ashexaethyl-Diquat-5), and maintaining said mixture under crystallizationconditions until the required zeolite is formed. The synthesis mixturehas a composition within the following ranges: SiO₂:Al₂O₃ of 20 to200:1, preferably 40 to 100:1; H₂O:SiO₂ of 10 to 200:1, preferably of 20to 50:1; OH⁻:SiO₂ of 0 to 3:1, preferably 0.1 to 0.5:1; Z:SiO₂ of 0 to3:1, preferably of 0.1 to 2:1, where Z is an alkali metal cation; R:SiO₂of 0.01 to 2:1, preferably of 0.1:1, where R is HEPD, preferably itsdibromide salt. Crystallization of zeolite ZSM-57 may be carried outunder either static or stirred conditions. A useful range oftemperatures for crystallization is from 80° C. to 350° C. for a time of12 hours to 200 days. Thereafter, the crystals are separated from theliquid and recovered. The synthesis of the zeolite crystals is said tobe facilitated by the presence of at least 0.01 wt percent, preferably0.10 wt %, and still more preferably 1 wt %, seed crystals (based ontotal weight) of crystalline product.

U.S. Pat. No. 4 873 067 further illustrates the preparation of boron,chromium, iron and/or gallium-containing zeolite ZSM-57 by a methodcomprising preparing a mixture containing sources of alkali metal ions,an oxide of silicon, an oxide of aluminium, a source of boron, chromium,iron and/or gallium, water and HEPD, and maintaining said mixture undercrystallization conditions until the required zeolite is formed.

The methods described in these documents all use HEPD as organicdirecting agent (template).

This material is, however, expensive and not commercially available. Useof the material at the lower end of the range mentioned in EP-A-174 121to minimize cost results in lower yields, while reducing the watercontent of the synthesis mixture increases synthesis times, therebyreducing batch yield.

SUMMARY OF THE INVENTION

We have now found that the preparation of crystalline molecular sieves,referred to for simplicity below as zeolites, of the MFS structure typeis facilitated when a mixture of HEPD and an additional organic moleculeis used as structure-directing agent.

Accordingly, the present invention provides a process for themanufacture of a crystalline molecular sieve of the MFS structure type,which comprises hydrothermal treatment of a synthesis mixture containingsources of alkali metal ions, of aluminium, and of silicon, water, anN,N,N,N′,N′,N′-hexaethylpentane diammonium salt (HEPD), hereinafter R₁,and R₂, an amine of formula NR¹R²R³ or a quaternary ammonium compound offormula R¹R²R³R⁴NX, wherein R¹, R², R³, or R⁴, which may be identical ordifferent, each independently represent a hydrogen atom, a linear alkylgroup having from 1 to 8 carbon atoms, a branched alkyl group havingfrom 3 to 8 carbon atoms, or a cycloalkyl group having 5 or 6 carbonatoms, at least one of R¹, R², R³, and if present R⁴, being other thanhydrogen, and X represents an anion. Mixtures of two or more compoundsR₁ may be used. Mixtures of two or more compounds R₂ may also be used.These may be mixtures of two or more amines, or of two or morequaternary compounds, or of one or more amines and one or morequaternary compounds.

DESCRIPTION OF THE INVENTION

The use of a mixture of HEPD, R₁, and of an additional organic moleculeR₂ instead of R₁ alone facilitates the preparation of zeolites of theMFS structure type in several respects.

We have found that a synthesis mixture containing low amounts of R₁ caneffectively produce zeolites of the MFS structure type when theadditional organic molecule is present in the synthesis mixture. Itspresence affords the MFS structure zeolite in higher yields than R₁alone, even at low total organic molecule to silica ratios.Crystallization occurs faster, even under static conditions and in somecases without using seeds when the mixture of organic directing agentsis used.

The invention also accordingly provides the use of the compound R₂ inthe synthesis of an MFS structure type molecular sieve.

As amine for use as a second organic molecule there may be mentioned,for example, mono, di- and tri-methylamine, mono-, di- andtriethylamine, mono-, di- and tri propylamines, mono-, di- andtrihexylamines, mono-, di- and triheptylamines, mono-, di- andtrioctylamines, cyclopentylamine and cyclohexylamine. Advantageously,the amine is a triamine, i.e., none of R¹, R², and R³ representshydrogen. Preferably, the amine of formula NR¹R²R³ is selected fromtrimethylamine, triethylamine and a tripropylamine; most preferably itis triethylamine. Advantageously, the quaternary ammonium compoundcorresponds to one of the above amines, and is preferably atetralkylammonium compound, preferably a tetramethyl-, tetraethyl-, ortetrapropyl-ammonium compound, a tetra ethylammonium compound being mostpreferred. As examples of the anion there may be mentioned halide,especially chloride or bromide, and hydroxide. Mixtures of thesecompounds may be used, as indicated above.

The invention more especially provides a process for the manufacture ofa crystalline molecular sieve of the MFS structure type which comprisessubjecting to hydrothermal treatment a synthesis mixture having acomposition within the molar ranges of

  20 to 200 SiO₂:Al₂O₃   10 to 200 H₂O:SiO₂    0 to 3 OH⁻:SiO₂    0 to 3M⁺:SiO₂  0.01 to 2 R₁:SiO₂ 0.005 to 2 R₂:SiO₂wherein M⁺ represents an alkali metal, R₁ represents HEPD, and R₂ theadditional organic molecule defined above.

Preferred molar ranges are

   40 to 100 SiO₂:Al₂O₃    15 to 50 H₂O:SiO₂   0.1 to 0.5 OH⁻:SiO₂   0.1to 2 M⁺:SiO₂  0.01 to 1 R₁:SiO₂ 0.0075 to 2 R₂:SiO₂

More preferably, the molar ratio of R₁:SiO₂ is within the range 0.01 to1:1 and the molar ratio of R₂:SiO₂ is within the range of from 0.01 to2:1. Most preferably the molar ratios of R₁:SiO₂ and R₂:SiO₂ are bothwithin the range of from 0.02 to 1:1.

Advantageously the R₁+R₂:SiO₂ molar ratio is at least 0.025:1, andpreferably within the range 0.025:1 to 10:1, more preferably 0.025:1 to5:1, and most preferably within the range of 0.025 to 3:1. Preferredmixtures are of the HEPD dibromide and triethylamine ortetraethylammonium bromide or hydroxide, and preferred ratios are withinthe range 1:3 to 1:1.

The hydrothermal treatment may be carried out under the usual ZSMsynthesis conditions. Advantageously used are temperatures within therange of from 100° C. to 200° C., preferably from 140° C. to 180° C.,and conveniently at about 160° C. Temperature may be increased,gradually or stepwise, during treatment. Advantageously, a time withinthe range of from 70 to 200 hours, preferably within the range of from70 to 150 hours, and conveniently from 3 to 8 days, is employed, lowertemperatures corresponding to longer times.

Treatment may be carried out with or without agitation, for examplestirring or tumbling (rotating the vessel about a horizontal axis).

It has been found that for certain synthesis mixture compositions, apure MFS structure type material is more readily obtained when synthesisis carried out with agitation. For a composition that gives purematerial whether synthesis is carried out with or without agitation,crystal size is normally greater if the synthesis is carried out withoutagitation.

The synthesis may be aided by seeds from a previous synthesis, the seedsbeing advantageously colloidal or near-colloidal. Seeds of a differentstructure type, especially LEV, may be used. The preparation ofcolloidal LEV seeds is described in International application WO00/06494. Seeds are advantageously present in a proportion of from0.001% to 1%, preferably 0.01% to 0.1%, by weight, based on the totalweight of synthesis mixture. For certain synthesis mixtures, a pure MFSstructure type material is more readily obtained with seeding.

The procedure may include an ageing period, either at room temperatureor at a moderately elevated temperature, lower than that used for thehydrothermal treatment.

The sources of the various elements required in the final product may beany of those in commercial use or described in the literature, as maythe method of preparation of the synthesis mixture.

For example, the source of silicon may be a silicate, e.g., an alkalimetal silicate, a tetraalkyl orthosilicate, or, a high surface areasilica, for example one sold by Degussa under the trade names Aerosil orUltrasil, or preferably, an aqueous colloidal suspension of silica, forexample one sold by E.I. du Pont de Nemours under the trade name Ludox.

The source of aluminium is preferably aluminium sulphate or hydratedalumina. Other aluminium sources include, for example, otherwater-soluble aluminium salts, sodium aluminate, or an alkoxide, e.g.,aluminium isopropoxide, or aluminium metal, e.g., in the form of chips.

The alkali metal is advantageously potassium or sodium, the sodiumsource advantageously being sodium hydroxide or sodium aluminate.

The organic molecules are advantageously supplied in the form of anaqueous solution.

The direct product of the synthesis described above may be calcined,cation-exchanged, and otherwise treated as is known in the art. Alkalimetal cations in the as-prepared or calcined form may be removed, forexample by treatment with concentrated acids, e.g., HCl, or with afugitive base, e.g., an ammonium compound, to provide the material inits hydrogen form.

The products of the invention, if required after cation exchange and/orcalcining, have utility as catalyst precursors, catalysts, andseparation and absorption media. They are especially useful in numerousorganic, e.g., hydrocarbon, compound conversions, separations andabsorptions. They may be used alone, or in admixture with othermolecular sieves, in particulate form, supported or unsupported, or inthe form of a supported layer. Hydrocarbon conversions include, forexample, cracking, reforming, hydrofining, aromatization,oligomerization (e.g., di- and trimerization, especially of olefinshaving 3 to 6 carbon atoms, more especially butene trimerization),isomerization, dewaxing, and hydrocracking (e.g., naphtha to lightolefins, higher to lower molecular weight hydrocarbons, alkylation,transalkylation, disproportionation or isomerization of aromatics).Other conversions include the reaction of alcohols with olefins and theconversion of oxygenates to hydrocarbons.

EXAMPLES

The following numbered examples, in which all parts are percentages areby weight unless otherwise indicated, illustrate the invention.Percentage yields are based on the total weight of synthesis mixture.

To form HEPD, the following procedure was used: 1 mole of1,5-dibromopentane and 2 moles of triethylamine were dissolved inethanol and refluxed overnight. The resulting solution was concentratedand finally evaporated to dryness under vacuum at 35° C. The whiteproduct was recrystallized from ether and identified asN,N,N,N′,N′,N′-hexaethylpentane diammonium dibromide.

Examples A and B—Comparative

150.02 parts of colloidal silica (Ludox HS40) and 400.21 parts of waterwere formed into an initial mixture (A) with stirring. 43.41 parts ofN,N,N,N′,N′,N′ hexaethylpentane diammonium dibromide (hereinafter “HEPD”or R₁) were dissolved in 97.36 parts of water and added to mixture (A),together with 11.53 parts of rinse water, and mixed for 5 minutes. Asolution of 11.14 parts of Al₂(SO₄)₃.18H₂O and 16.25 parts NaOH (Baker,98.6%) in 99.97 parts of water, followed by 12.10 parts of rinse water,was added and mixed for a further 5 minutes to form a smooth gel with amolar composition of:

-   2Na₂O:R₁:0.17 Al₂O₃:10 SiO₂:400 H₂O

Example A

The synthesis mixture was poured into a stainless steel autoclaveequipped with a stirrer and heated with stirring over the course of 6hours to 160° C., and maintained at that temperature with stirring for144 hours. The solid product was recovered from the reaction mixture,washed, and dried at 120° C. Yield 6.7%. XRD analysis of the materialshowed it to be ZSM-57, a zeolite of the MFS structure type.

Example B

A similar synthesis mixture was heated for 240 hours at 160° C. withoutstirring. No pure material was obtained, instead a mixture of MOR andMFS structure type materials and quartz resulted.

Example 1

A synthesis mixture was prepared as described in Comparative Example A,except that the proportion of HEPD used was reduced to 0.25 moles per 10moles SiO₂, and 0.25 moles of triethylamine (TEA) per 10 moles SiO₂ wereadded to the synthesis mixture as prepared in Example A. The molarcomposition of the gel was:

-   1.81 Na₂O:0.25 HEPD:0.25 TEA:0.17 Al₂O₃:10 SiO₂:401 H₂O

The synthesis mixture was poured into an autoclave and heated to 160° C.over the course of 2 hours, and maintained at that temperature for 96hours, without agitation. A solid product was recovered, washed, anddried at 120° C.

XRD analysis of the material showed it to be pure ZSM-57, the yield was6.55%.

Examples 2 and 3

In these examples, small proportions of LEV seeds were added to thesynthesis mixture.

In Example 2, the synthesis mixture was prepared as in Example 1, butusing 0.75 moles of TEA per 10 moles SiO₂, and then 205 ppm LEV seeds,based on the total weight of mixture, were added, with shaking for 10minutes. Molar composition of gel:

-   1.80 Na₂O:0.25 HEPD:0.75 TEA:0.17 Al₂O₃:10 SiO₂:400 H₂O, with 205 wt    ppm LEV seeds.

In Example 3, a synthesis mixture was prepared as in Example 2, butusing 200 moles H₂O per 10 SiO₂, and 201 ppm LEV seeds. Molarcomposition of gel:

-   1.80 Na₂O:0.25 HEPD:0.75 TEA:0.17 Al₂O₃:10 SiO₂:200 H₂O, with 201    ppm LEV seeds.

Both synthesis mixtures were heated to 160° C. over the course of 2hours, without stirring. In Example 2, the 160° C. temperature wasmaintained for 96 hours, and in Example 3 for 144 hours, both withoutagitation. Both Examples gave ZSM-57, Example 2 in 6.63% yield, Example3 in 11.47% yield.

Examples 4 and 5

These examples employ synthesis mixtures that contain 0.25 moles oftetraethylammonium hydroxide (TEAOH) and 0.25 moles of HEPD per 10 molesSiO₂, in a more concentrated synthesis mixture than that of Example 1(200 moles of H₂O per 10 SiO₂), with LEV seeds added.

A synthesis mixture was prepared having the molar composition:

-   1.90 Na₂O:0.25 HEPD:0.25 TEAOH:0.17 Al₂O₃:10 SiO₂:201 H₂O with 201    ppm LEV seeds.

The mixture was divided into two portions, each being heated to 160° C.over 6 hours and maintained at that temperature for 120 hours. Oneportion, Example 4, was not agitated, the other, Example 5, was tumbledat 120 rpm throughout.

The solid products of both procedures were recovered, washed and driedovernight at 120° C. XRD analysis showed both were ZSM-57. Yields:Example 4: 10.88%, Example 5: 9.57%.

In comparison experiments (Examples C and D), an unseeded synthesismixture otherwise of the same molar composition was subjected tohydrothermal treatment at the same temperature. The static portion,Example C, showed

little crystallinity after 192 hours, while the tumbled portion, ExampleD, had yielded only a mixture of mordenite and α-quartz after 192 hours.

Example 6

This example employs a synthesis mixture containing 0.25 moles oftetraethylammonium bromide (TEABr) and 0.25 moles of HEPD per 10 molesSiO₂, without seeding.

A synthesis mixture was prepared having the molar composition:

-   2.00 Na₂O:0.25 HEPD:0.25 TEABr:0.17 Al₂O₃:10 SiO₂:400.1 H₂O

The mixture was aged at room temperature for 24 hours, heated over 6hours to 160° C., maintained at that temperature for 96 hours, cooled toroom temperature and aged for a further 24 hours, with stirringthroughout. The resulting mixture was centrifuged, the solids washed,and dried overnight at 120° C. The product was pure ZSM-57, yield 6.4%.

Example 7

This example employs the same organic constituents as the previousexample, and a different silica source, a high purity silica solid byDegussa under the trade name Ultrasil VN3SP-PM.

A synthesis mixture was prepared having the molar composition:

-   1.96 Na₂O:0.25 HEPD:0.25 TEABr:0.17 Al₂O₃:10 SiO₂:202 H₂O, with 198    ppm LEV seeds.

The mixture was heated over 2 hours to 160° C., and maintained at thattemperature for 96 hours, all without stirring. The resulting mixturewas centrifuged, the solids washed, and dried overnight at 120° C. Theproduct was pure ZSM-57, yield 11.6%.

Example 8

A synthesis mixture was prepared having the molar composition:

-   1.90 Na₂O:0.25 HEPD:0.25 TEAOH:0.17 Al₂O₃:10 SiO₂:202 H₂O and 202    ppm LEV seeds.

The mixture was heated over 6 hours to 160° C., and maintained at thattemperature for 130 hours, all with stirring. The resulting mixture wascentrifuged, and the solids washed and dried for 60 hours at 120°. Theproduct was pure ZSM-57, yield 9.28%.

In a comparison experiment (Example E), the molar proportion of TEAOHwas doubled, to 0.50 per 10 SiO₂; the product was MFS in admixture withMOR and α-crystobalite.

Example 9

In this example, the same molar proportion of TEAOH, 0.50 per 10 SiO₂,as in Comparison Example E was used, but compensated by a lower molarproportion of Na₂O, 1.40 per 10 SiO₂.

A synthesis mixture was prepared having the molar composition:

-   1.40 Na₂O:0.25 HEPD:0.50 TEAOH:0.17 Al₂O₃:10 SiO₂:200 H₂O and 200    ppm LEV seeds.

The mixture was heated over 6 hours to 160° C. and maintained at thattemperature for 120 hours, all with stirring. The resulting mixture wascentrifuged, the solids washed and dried overnight at 120° C. Theproduct was pure ZSM-57, of particle size about 1 μm, yield 12.5%.

1. A process for the manufacture of a crystalline molecular sieve of theMFS structure type, the process comprising hydrothermal treatment of asynthesis mixture containing: a) sources of alkali metal ions,aluminium, and silicon; b) water; c) R₁, anN,N,N,N′,N′,N′-hexaethylpentane diammonium salt; and d) R₂, an amine offormula NR¹R²R³ or a quaternary ammonium compound of formula R¹R²R³R⁴NX;wherein: i) R¹, R², R³, and R⁴, which may be identical or different,each independently represents: 1) a hydrogen atom, 2) a linear alkylgroup having from 1 to 8 carbon atoms, 3) a branched alkyl group havingfrom 3 to 8 carbon atoms, or 4) a cycloalkyl group having 5 or 6 carbonatoms, ii) at least one of R¹, R², and R³, and if present R⁴, beingother than hydrogen, and iii) X represents an anion.
 2. The process asclaimed in claim 1, wherein none of R¹, R², R³, and R⁴ is hydrogen. 3.The process as claimed in claim 1, wherein the amine comprises one ormore of trimethylamine, triethylamine, and tripropylamine.
 4. Theprocess as claimed in claim 1, wherein the quaternary ammonium compoundcomprises one or more of tetraethylammonium halide, andtetraethylammonium hydroxide.
 5. The process as claimed in claim 4,wherein the halide comprises one or more of bromide and chloride.
 6. Theprocess as claimed in claim 1, wherein: a) the synthesis mixture has acomposition within the molar ranges of:   20 to 200 SiO₂:Al₂O₃   10 to200 H₂O:SiO₂    0 to 3 OH⁻:SiO₂    0 to 3 M⁺:SiO₂  0.01 to 2 R₁:SiO₂0.005 to 2 R₂:SiO₂

 and b) M⁺ represents an alkali metal cation.
 7. The process as claimedin claim 6, wherein the synthesis mixture has a composition within themolar ranges of:    40 to 100 SiO₂:Al₂O₃    15 to 50 H₂O:SiO₂   0.1 to0.5 OH⁻:SiO₂   0.1 to 2 M⁺:SiO₂  0.01 to 1 R₁:SiO₂ 0.0075 to 2 R₂:SiO₂


8. The process as claimed in claim 6, wherein the molar ratio of R₁:SiO₂is within the range of from 0.01 to 1:1 and the molar ratio of R₂:SiO₂is within the range of from 0.01 to 2:1.
 9. The process as claimed inclaim 6, wherein the molar ratios of R₁:SiO₂ are within the range offrom 0.02 to 1:1.
 10. A process as claimed in claim 6, wherein the molarratio of (R₁+R₂₎:SiO₂ is within the range of 0.025 to 3:1.
 11. Theprocess as claimed in claim 1, wherein the silicon source is colloidalsilica, the aluminium source is aluminium sulphate, and the alkali metalsource is sodium hydroxide.
 12. The process as claimed in claim 1,wherein the synthesis mixture also contains seed crystals.
 13. Theprocess as claimed in claim 12, wherein the seed crystals are of LEVstructure type.
 14. The process as claimed in claim 12, wherein theproportion of seeds is within the range of 0.001% to 1% by weight, basedon the weight of synthesis mixture.
 15. The process as claimed in claim1, carried out at a temperature within the range 100° C. to 200° C. 16.The process as claimed in claim 1, carried out for from 70 to 200 hours.17. The process as claimed in claim 1, carried out under staticconditions.
 18. The process as claimed in claim 1, carried out underagitated conditions.
 19. The process as claimed in claim 1, wherein thecrystalline molecular sieve produced is ZSM-57.
 20. A crystallinemolecular sieve of the MFS structure type, containing R₁ and R₂,wherein: a) R₁ is an N,N,N,N′,N′,N′-hexaethylpentane diammonium salt; b)R₂, an amine of formula NR¹R²R³ or a quaternary ammonium compound offormula R¹R²R³R⁴NX, wherein: i) R¹, R², R³, and R⁴, which may beidentical or different, each independently represents: 1) a hydrogenatom, 2) a linear alkyl group having from 1 to 8 carbon atoms, 3) abranched alkyl group having from 3 to 8 carbon atoms, or 4) a cycloalkylgroup having 5 or 6 carbon atoms, and at least one of R¹, R², and R³,and if present R⁴, being other than hydrogen, and ii) X represents ananion.
 21. The crystalline molecular sieve as claimed in claim 20,wherein component R₂ is selected from one or more of a trimethylamine, atriethylamine, a tripropylamine, a tetraethylammonium salt, and atetraethylammonium hydroxide.
 22. The crystalline molecular sieve asclaimed in claim 20, which is ZSM-57 contains residual R₁ and R₂. 23.The crystalline molecular sieve as claimed in claim 20, which has beensubjected to calcination and/or ion exchange.
 24. A method ofhydrocarbon conversion, the method comprising contacting the hydrocarbonand a crystalline molecular sieve of the MFS structure type, underconditions sufficient to effect conversion of the hydrocarbon, whereinthe crystalline molecular sieve of the MFS structure type contains: a)R₁, an N,N,N,N′,N′,N′-hexaethylpentane diammonium salt; and b) R₂, anamine of formula NR¹R²R³ or a quaternary ammonium compound of formulaR¹R²R³R⁴NX; wherein: i) R¹, R², R³, and R⁴, which may be identical ordifferent, each independently represents: 1) a hydrogen atom, 2) alinear alkyl group having from 1 to 8 carbon atoms, 3) a branched alkylgroup having from 3 to 8 carbon atoms, or 4) a cycloalkyl group having 5or 6 carbon atoms, and ii) at least one of R¹, R², and R³, and ifpresent R⁴, being other than hydrogen, and iii) X represents an anion.25. The method of claim 24 wherein the hydrocarbon conversion isselected from cracking, reforming, hydrofining, aromatization,oligomerization, isomerization, dewaxing and hydrocracking.
 26. Themethod of claim 25, wherein the oligomerization is selected fromdimerization and trimerization of olefins having 3 to 6 carbon atoms.27. The method of claim 26, wherein the oligomerization is trimerizationof butene.
 28. The method of claim 25, wherein the hydrocracking isselected from: (1) naphtha to light olefins, (2) higher to lowermolecular weight hydrocarbons, (3) alkylation of aromatics, (4)transalkylation of aromatics, (5) disproportionation of aromatics, and(6) isomerization of aromatics.
 29. A method of reacting an alcohol andand an olefin, the method comprising contacting the alcohol and olefinand a crystalline molecular sieve of the MFS structure type, underconditions sufficient to effect the reaction of the alcohol and theolefin, wherein the crystalline molecular sieve of the MFS structuretype contains: a) R₁, an N,N,N,N′,N′,N′-hexaethylpentane diammoniumsalt; and b) R₂, an amine of formula NR¹R²R³ or a quaternary ammoniumcompound of formula R¹R²R³R⁴NX; wherein: i) R¹, R², R³, and R⁴, whichmay be identical or different, each independently represents: 1) ahydrogen atom, 2) a linear alkyl group having from 1 to 8 carbon atoms,3) a branched alkyl group having from 3 to 8 carbon atoms, or 4) acycloalkyl group having 5 or 6 carbon atoms, and ii) at least one of R¹,R², and R³, and if present R⁴, being other than hydrogen, and iii) Xrepresents an anion.
 30. A method of converting an oxygenate to ahydrocarbon, the method comprising contacting the oxygenate and acrystalline molecular sieve of the MFS structure type, under conditionssufficient to effect conversion of the oxygenate, wherein thecrystalline molecular sieve of the MFS structure type contains: a) R₁,an N,N,N,N′,N′,N′-hexaethylpentane diammonium salt; and b) R₂, an amineof formula NR¹R²R³ or a quaternary ammonium compound of formulaR¹R²R³R⁴NX; i) wherein R¹, R², R³, and R⁴, which may be identical ordifferent, each independently represents: 1) a hydrogen atom, 2) alinear alkyl group having from 1 to 8 carbon atoms, 3) a branched alkylgroup having from 3 to 8 carbon atoms, or 4) a cycloalkyl group having 5or 6 carbon atoms, and ii) at least one of R¹, R², and R³, and ifpresent R⁴, being other than hydrogen, and iii) X represents an anion.